1. Field of the Invention.
This invention relates to a passive range of motion (PROM) device. More particularly, this invention relates to a glove for preventing and curing contracture of the hand muscles.
2. Description of the Prior Art.
Many diseases and injuries cause temporary or permanent paralysis of the hand. Without constant movement or exercise, the muscles shrink and contract. A very common physical problem affecting people such as stroke victims, people with nerve injury or brain damage, or those who have had a limb immobilized due to illness or injury, is contracture. Contracture results when the nerve supply to a muscle is blocked or cut off. The muscle fibers tend to shorten and can often shorten to the point where the affected part of the body becomes extremely contorted. For example, where the nerve supply to hand muscles is cut off, the hand muscles begin to contract causing the thumb and fingers to coil inward. Later, in full contracture, the hand becomes a tightly clenched fist and the wrist and arm coil inward. Contracture causes poor circulation, pressure sores, and infections.
One way to prevent contracture is to stretch the affected muscles daily. Stretching is achieved through passive exercise which means that the muscle is exercised without any effort on the part of the patient. Passive exercises, or passive range of motion (PROM) exercises must be performed several times daily to prevent contracture. Unfortunately, having PROM exercises administered several times a day requires a great amount of time (approximately one-half hour per session for a quadriplegic). Therefore, a nursing assistant, who is caring for eight or nine patents, for example, may not have a chance to perform it. Additionally, a physical therapist can and should be used to perform the PROM exercises; but, because of the time involved this is very expensive.
Several techniques have been developed to prevent, or slow, the muscle contractions. Many of these involve static stretching in which the affected limb is strapped into a cast or splint in the stretched position. A common method for performing these static stretches is through the use of a wrist-hand orthesis (W.H.O.). However, the effectiveness of the W.H.O. is unclear. Without movement, the muscles continue to contract and, where the affected limb is an arm, the muscles continue to curl the fingers and bend the wrist.
Additionally, the W.H.O. presents several problems. The patient may not get an adequate blood supply because, as the contractions advance, the W.H.O. straps become tighter and tighter. In addition, the W.H.O. is a rigid splint and cannot be adapted to different patients with various degrees of contracture. Another technique which helps prevent contracture is strong electrical stimulation. However, this is very expensive and is generally only used on patients who are expected to recover the use of the affected limb.
Several other techniques are also used which actually move and flex the joints in the affected limb. Many of these use air or fluid pressure to inflate balloons which tend to push or pull the curled limb into a straightened position.
There is a continuing need for passive range of motion devices which offer simple and quick application, which are easy to produce, and which are suitable for use by patients in various states of contracture.